Precision Devices PD.1850/2

18" · 8 Ω · 800 W · 96.7 dB

Thiele-Small parameters

Nominal size	18"
Impedance	8 Ω
Fs	33.1 Hz
Qts	0.24
Qes	0.24
Qms	15.4
Vas	203.84 L
Sd	1164 cm²
Xmax	11.1 mm
Re	5.2 Ω
Bl	31 T·m
Mms	215.2 g
Pe	800 W
Sensitivity	96.7 dB

Alignment hint

EBP	138 · ported
Sealed Vb (Qtc ≈ 0.71)	≈ 26.5 L

EBP > 100: favours a ported (bass-reflex) alignment.

Rules of thumb from T/S parameters only. Verify against a real simulation before cutting wood.

Substitute candidates

Driver	Fs (Hz)	Qts	Vas (L)	Xmax (mm)	Sens (dB)	Fit	Notes	Compare
Precision Devices PD.185C003-8	33 -0.1	0.24 =	224 +20.16	11 -0.1	97.3 +0.6	close	Xmax 11 mm < 11.1 mm: lower excursion-limited SPL	+
Precision Devices PD.185N02	35.2 +2.1	0.24 =	178.28 -25.56	12 +0.9	96.8 +0.1	close		+
Beyma 18QLEX1600Fe	30 -3.1	0.23 -0.01	195 -8.84	13 +1.9	97 +0.3	close		+
Beyma 18QLEX1600Fe	31 -2.1	0.25 +0.01	177.2 -26.64	13 +1.9	96 -0.7	close	4 Ω vs 8 Ω: amp load changes	+
Fane IMPERIUM 18NDXL	33 -0.1	0.295 +0.05	203 -0.84	12 +0.9	95.7 -1	close		+
B&C 18DS100	32 -1.1	0.24 =	157 -46.84	14 +2.9	98 +1.3	close	4 Ω vs 8 Ω: amp load changes	+
18 Sound 18NLW4100	29 -4.1	0.27 +0.03	207 +3.16	15 +3.9	97 +0.3	close	4 Ω vs 8 Ω: amp load changes	+
RCF LF 18X451	30 -3.1	0.278 +0.04	220 +16.16	10.7 -0.4	96.8 +0.1	close	Xmax 10.7 mm < 11.1 mm: lower excursion-limited SPL	+
RCF LF18N451	31 -2.1	0.24 =	245 +41.16	9 -2.1	97.5 +0.8	close	Xmax 9 mm < 11.1 mm: lower excursion-limited SPL	+
Beyma 18QLEX1600/Fe	30 -3.1	0.231 -0.01	195 -8.84	8.3 -2.8	97.2 +0.5	close	Xmax 8.3 mm < 11.1 mm: lower excursion-limited SPL	+

Compare the closest 3 against the PD.1850/2 →

Ranked on parameter similarity only (Qts, Fs, Vas, Xmax, sensitivity). Same nominal size required. A hint, not a simulation, model the swap before cutting or buying.

Used in enclosures (0)

No enclosure in the catalog uses this driver yet.